A wide variety of manufacturing processes exist which require transferring a wire through a wire processing zone in order to coat or otherwise process the wire. For instance, several manufacturing processes exist for coating a wire substrate with a superconductor material. Examples of such processes are disclosed in co-pending U.S. patent applications Ser. No. 523,221 for an invention entitled "Melt Texturing of Long Superconductor Fibers"; and Ser. No. 528,707 for an invention entitled "Method for Electroplating of Yttrium Metal in Nonaqueous Solutions", both of which are assigned to the same assignee as the present invention.
Typically, processes such as the ones mentioned above require that the wire substrate be precisely drawn through a processing zone without radially supporting the wire. The wire ordinarily is not radially supported because radial support structure would otherwise interfere with the wire processing apparatus. Consequently, to ensure that the wire follows a substantially straight, precise path through the processing zone, it is necessary that the wire be kept in tension as the wire is drawn through the zone.
It is often the case that superconductor fabrication and other wire processing procedures require the use of a relatively thin and sometimes fragile metal wire or ceramic substrate. This can be unfortunate because, as is well-known, thin, fragile wire substrates, as well as ceramic superconductor substrates, typically have a low tensile strength. Thus, the tension of the substrate must be kept low enough to preclude breakage or deformation of the substrate during processing. On the other hand, as discussed above, the substrate must be kept in sufficient tension to keep the wire substrate radially aligned as the wire substrate passes through the processing zone. The present invention recognizes that the tension of a wire substrate which is passed through a processing zone can be established to ensure radial alignment of the wire in the zone, while avoiding wire breakage or deformation.
Accordingly, it is an object of the present invention to provide a system which establishes a predetermined tension of a wire during a wire processing procedure. Yet another object of the present invention is to provide a system which establishes the tension of a wire to preclude wire breakage or deformation while the wire passes through a processing zone. Finally, it is an object of the present invention to provide a wire tension control system which is relatively easy to use and comparatively cost-effective to manufacture.